1. Field of the Invention
The present invention relates to a mounting for one or more articles which are movable on the mounting between accessible and inaccessible positions. More specifically, the present invention relates to a mounting for an article which permits movement of the article from an inaccessible location in back of a wall or within an enclosure to an accessible location in front of the wall or outside of the enclosure. The present invention constitutes an improvement of, and a novel departure from, the mounting disclosed in U.S. Pat. No. 4,250,357, issued Feb. 10, 1981. Viewed even more specifically as an improvement of the mounting disclosed in the aforementioned United States patent, the present invention relates to a mounting for an electrical fuse or other electrical device which is movable on the mounting between an inaccessible position within an enclosure whereat the fuse is connected to an electrical circuit and an accessible position outside the enclosure, whereat the fuse is disconnected from the electrical circuit.
In many work environments, various articles or devices are used in normally inaccessible locations. Such inaccessible locations may typically be behind a wall which may form a portion of some type of enclosure. Often, depending upon the work environment, it may become necessary from time to time to inspect or replace the article or device for a variety of reasons. Either because of the size or weight of the article or device, or because of the nature of the environment behind the wall or within the enclosure, it may be desirable that movement of the article or device to an accessible location be achieved indirectly by manipulation and movement of a mounting for the article or device.
Considering high-voltage electrical apparatus of the so-called pad-mounted or metal-enclosed variety as exemplary of the work environment in which the mounting of the present invention may be used, the article or device may constitute an electrical device or component such as a fuse, a switch, a transformer, circuit breaker or a meter. In the past, typical pad-mounted and metal-enclosed gear has included a metal enclosure having one or more access doors on the exterior thereof. Opening of one or more of these doors, as well as of any doors, screens or barriers therebehind, renders accessible the electrical device or component. In a variation of typical pad-mounted or metal-enclosed gear, often referred to as "grounded front" or "dead front" gear, the opening of the exterior doors does not immediately render accessible the electrical device or component within the enclosure. What is rendered immediately accessible upon opening the exterior doors are various walls, panels, and other devices, such as electrical connectors or the like, the immediately exposed surfaces of which are all at the ground potential of the enclosure. Theoretically, then, a workman in the vicinity of this variety of high-voltage gear may safely contact either the enclosure or any of the items exposed by opening the exterior doors, because, presumably, none of these items are at an elevated potential. In so-called "grounded front" gear, then, access to the electrical devices or components within the enclosure requires further manipulation which typically involves or requires deenergization of the involved device or component so that the enclosure may be penetrated and the device or component may be removed by the workman.
Especially in the field of high-voltage electrical gear, safety is of prime importance. Accordingly, also of prime importance with such high-voltage gear is the prevention of the intentional or unintentional ingress into those portions of the enclosure which contain energized live parts when the electrical device or component of interest is being removed for inspection, replacement or the like. A primary object, therefore, of the present invention, is to provide a mounting for an electrical device or component, such as a high-voltage fuse, which may be moved between an inaccessible position within the enclosure and an accessible position outside of the enclosure, and which, in both positions of the device or component minimizes or absolutely eliminates any points of ingress into those portions of the enclosure whereat energized live parts could be intentionally or inadvertently contacted by a workman.
2. Brief Discussion of the Prior Art
U.S. Pat. No. 4,250,357 issued Feb. 10, 1981 discloses a fuse mounting. In that patent, a plurality of panels having front sides and back sides have fuses mounted to the back sides thereof. The panels normally cover openings through a wall of an enclosure and position the fuses in an inaccessible location within the enclosure. Each panel is hinged at its bottom to the enclosure wall. In order to gain access to each fuse, its panel is unlatched and is rotated outwardly and downwardly on its hinge until the fuse is accessibly located in a horizontal position immediately in front of the opening normally covered by the panel. When any panel is in this rotated position, its opening is uncovered. A portion of a body of a workman or a tool may inadvertently enter the enclosure through the uncovered opening during the time the fuse is being removed or inspected. If energized live parts are present within the enclosure and may be contacted through the uncovered opening, and if the electrical gear is intended to be so-called "grounded front" or "dead front" gear, the safety of the workman has been compromised to some extent by the presence of the uncovered openings. Accordingly, an object of the present invention is to provide a fuse mounting for electrical gear in which the fuse is movable between an inaccessible position within an enclosure and an accessible position outside of the enclosure, and wherein an opening in a wall of the enclosure is covered or blocked in both positions of the fuse.
The following United States patents also disclose a variety of panel-mounted electrical devices or components, wherein a panel is hinged or similarly connected to the wall of an enclosure to move the electrical device or component between an inaccessible location within the enclosure and an accessible location outside of the enclosure: U.S. Pat. Nos. 2,636,955 to George, issued Apr. 28, 1953; 2,565,314 to Lewis, issued Aug. 21, 1951; 2,268,943 to Johansson, issued Jan. 6, 1942; 2,128,648 to Johannson, issued Aug. 30, 1938; 2,020,913 to Schramm, issued Nov. 12, 1935; 1,826,370 to Schwarz, et al, issued Oct. 6, 1931; 1,561,239 to Jennings, issued Nov. 10, 1925; 1,594,010 to Gaspari, issued July 27, 1926; and 1,351,043 to Kries, issued Aug. 31, 1920. Some of these patents are similar to the '357 patent in that a hinged panel is rotated to move an electrical component mounted thereon between inaccessible and accessible locations, and when the component is in its accessible position, an opening into the interior of a housing or behind a wall is left opened and uncovered. Such patents include those to George, Johannson, Schramm, Schwarz and Gaspari. In others of these patents, a blocking member is connected to the panel so that movement of the panel moves an electrical component or device out of the enclosure or in front of a wall thereof, but the blocking member moves simultaneously to cover the opening. These patents include those to Lewis, Jennings, and Kries.
As discussed below, none of the above-noted prior art patents, including the '357 patent, are structurally and functionally similar to the mounting of the present invention, and merely provide a general overview of various techniques for moving electrical devices or components between inaccessible and accessible locations.